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Baja 250es 11-08-2020 10:29 AM

Build
 
Ok so back to measurements for head gasket
https://cimg2.ibsrv.net/gimg/www.off...cf41b2c84e.jpg
It shows between 30k and 31k

Baja 250es 11-08-2020 10:36 AM

Build
 
https://cimg2.ibsrv.net/gimg/www.off...182910876d.jpg
This is what I'm installing

underpsi68 11-08-2020 10:46 AM


Originally Posted by Baja 250es (Post 4764840)
Ok so back to measurements for head gasket
https://cimg2.ibsrv.net/gimg/www.off...cf41b2c84e.jpg
It shows between 30k and 31k

did you rock the piston back and forth and take an average?

Baja 250es 11-08-2020 12:02 PM

Build
 
Yes 30 - 34

mcollinstn 11-08-2020 12:18 PM

Cut .034 off the block (zero deck). Then run .036-.039 gaskets.
Yes, it will increase compression, but the added turbulence from the "squish" benefits you MORE in both WIN/WIN categories. Power production AND detonation prevention.

Then, do some bowl work on the heads to unshroud the valves and add a few cc's to the chambers. Don't cut the heads unless they arent straight/flat.

I can't tell what carb that is.
Since you're running an aftermarket distributor, figure out your electronic advance and lock out the mechanical advance.
What ignition box/amp are you gonna run?



Baja 250es 11-08-2020 03:29 PM

Build
 
So I couldn't run a smaller gasket with the way the block is now and ignition is just factory setup still

Smitty275 11-08-2020 03:56 PM


Originally Posted by Baja 250es (Post 4764862)
So I couldn't run a smaller gasket with the way the block is now and ignition is just factory setup still

I can't speak for the ignition. But Cometic makes gaskets in about any thickness down to .027". They are the best on the market bar none. Using thinner gasket achieves same as cutting the block.

Baja 250es 11-08-2020 04:10 PM

Build
 
Thank u smitty that's what I thought but wasn't positive

Smitty275 11-08-2020 04:50 PM

Only issue with the .027" gasket is your still going to be above recommended max "quench" distance of .045". Unless you're going for every last ounce of performance in a timed racing situation I doubt you'll ever be able to measure the difference it power.

Baja 250es 11-08-2020 05:01 PM

Build
 
I'm not at all I just want it to be right no issues all season


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